Distribution of Alleles of β-Carotene Hydroxylase 1 Gene in Modern Genotypes of Zea mays L.

摘要

Abstract Carotenoids as the precursors in vitamin A synthesis are important micronutrients in human nutrition and animal feeding. β-Carotene is converted to vitamin A in an animal organism in the most efficient way. Increasing its content in mature maize grain is possible through applying the marker-associated breeding to identify genotypes with favorable allelic states of key carotenoid biosynthesis pathway genes. The β-carotene hydroxylase 1 gene is important for the accumulation of β-carotene in mature maize grain. One of its alleles blocks the conversion of β-carotene to β-cryptoxanthin and, thus, ensures the accumulation of β-carotene in?the mature grain. This favorable allele can be identified with the crtRB1-3'TE marker and the method of polymerase chain reaction as a 543-bp long amplicon in contrast to two other amplicons, 296-bp and 296-bp + 875-bp, unassociated with the increase in the β-carotene content in the grain at full maturity. It was established that 26.7 of 15 wide-known inbreds of foreign breeding and 21.6 of 153 prospective inbreds from the Dnipro Maize Breeding Program carried the β-carotene hydroxylase 1 gene allele (543-bp) favorable for the accumulation of β-carotene. This allele was identified among a majority of the analyzed maize subspecies, germplasms, and maturity groups, although the tendency towards an increase in its frequency was recorded among inbreds with the flint type of kernels, Lancaster and Lacaune germplasms, and among early and middle early inbreds. The current maize lines identified by the crtRB1-3'TE marker as carriers of the 543-bp allele in the β-carotene hydroxylase 1 gene are recommended for application in special marker-assisted breeding programs for increasing the β-carotene content in particular maize subspecies, groups of maturity, and germplasm types.